ADVANCED NUMERICAL SIMULATION OF MULTILANE TRAFFIC DYNAMICS USING A MODIFIED LWR MODEL WITH RAMPS

Abstract

The traffic flow modeling is a broad area of research that deals with the formulation of mathematical models to understand, predict and design the traffic flow systems. In this research a traffic flow simulation study is conducted by modifying the Lighthill, Whitham and Richards (LWR) model. The main objective is to include the ramps and multi-lanes in the model and analyze their effects on the road sections. The modified model is discretized by using finite difference method (FDM) and applied on a typical road section of length 4KM with four ramps (the road section is adjacent to Quaid-e-Awam University of Engineering, Science and Technology, Nawabshah). Based on the fact that the initial density of cars on road section, with ramps is usually unknown because of instantaneous change therefore a statistical data analysis was conducted. The initial data for a complete week from 7:00 am to 06:00 pm was obtained manually by counting the number of cars entering and leaving from the road sections. From, the data analysis the average values for initial density, velocity and flux were approximated. Then the model is implemented on MATLAB and simulated for the key parameters namely; density of cars, velocity, and flux at different time steps. The simultaneous effect of ramps and multi-lanes of road section were analyzed. The results are useful to predict high density regions on the road section at particular location and at specific time step. The research contributes to predict the behavior of traffic flow phenomenon with multi-lanes and ramps and provides directions for future research. The convergence, well-posed Ness and stability of the numerical schemes have also been analyzed. Finally, the results are validated by comparing with some existing methods and found to be realistic.